Gland adjusting mechanism



June 21; 1938. s. G. GREEN GLAND ADJUSTING-MECHANISM Filed Dec. 18, 1956Invent or E-amual 13-511211 EWMfl E Attur'ne Patented June 21, 1938UNITED STATES PATENT OFFICE 1 Claim.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 3700. G. 757) The invention described herein may be manufactured and usedby or for the Government for governmental purposes, without the paymentto me of any royalty thereon.

This invention relates to a gland adjusting mechanism.

In a water cooled machine gun having a recoiling barrel it is necessaryto provide packing for the movable joints in order to prevent leakage ofthe cooling medium which is contained in a jacket surrounding thebarrel. In the Browning type of machine gun the packing for the breechend of the barrel is held in place by a gland that can only be adjustedafter removing the water jacket.

The purpose of this invention is to arrange the barrel mounting so thatthe gland which is positioned internally of the assembly may be adjustedfrom an external position.

A further object is to provide a simple and emcient means for lockingthe gland in adjusted position.

To these and other ends, the invention consists in the construction,arrangement and combination of elements described hereinafter andpointed out in the claim forming a part of this specification.

A' practical embodiment of the invention is illustrated in theaccompanying drawing, wherein:

Fig. l is a longitudinal sectional View of a portion of a machine gunshowing the gland and gland locking means.

Fig. 2 is a view in elevation and partly in section of the gland.

Fig. 3 is a sectional view on the line 33 of Fig. 1.

Fig. 4 is a longitudial sectional view of a modified form of theinvention; and

Fig. 5 is a sectional view on the line 55 of 49 Fig. 4.

The machine gun illustrated in the drawing is of the Browning type andcomprises a receiver 5 having in its front end a trunnion block 6 formedwith a passage 1 for receiving a gun barrel whose 5 breech end isslidably supported in the bearing portion 9 of the block. Thisarrangement is similar to a cylinder and piston construction.

The passage forwardly of the bearing portion 9 is enlarged and spacedfrom the barrel and 50 forms an annular shoulder 10 for seating a ringII. A packing I2 is held against the ring II by an elongated gland l3which is inserted into the passage from the front end of the trunnionblock and is threaded to a tubular extension M of the block. When thegun is completely assembled the front end of the gland is disposedwithin a jacket l5 which is threaded on the extension l4 and contains afluid for cooling the gun barrel.

An annular row of teeth I6 is formed on the outer surface of the glandadjacent its rear end and when the gland is threaded in the block toconfine the packing I2, the teeth are generally in line with an aperturel! in the under side of the block. This aperture leads into alongitudinally extending slot l8 in the under side of the block. Aspring detent 19 carried by the block extends through the aperture l1and engages the teeth on the gland to lock the gland in position ofadjustment. I

When it is desired to rotate the gland to vary the compression of thepacking the detent I9 is moved out of locking engagement with the teeth,and a tool, such as a screw driver, is inserted through the aperture,brought into engagement with the teeth, and then moved tangentially ofthe gland to impart rotational movement to the gland and regulate thecompression of the packing l2. In the modification shown in Fig. 4 thegear teeth 20 on the gland 2| are engaged by a pinion 22 which ismounted on a shaft or pin 23 carried by the trunnion block 24. Thepinion is held against rotation by a spring detent 25 similar to thatshown in Fig.1.

I claim:

In a gun, a receiver having a bearing, a jacket for a cooling liquid onthe front of the receiver, a gun barrel slidably supported in thebearing of the receiver and extending forwardly through the jacket, apacking between the barrel and receiver and positioned forwardly of thebearing to establish a liquid seal, a gland threaded in the receiver toestablish a liquid seal and extending rearwardly to confine the packing,teeth on the outer side of the gland adjacent its rear end, and saidreceiver formed with an aperture giving access to the teeth of the glandfrom the exterior of the receiver.

SAMUEL G. GREEN.

